Disabling virtual nodes in an existing Solr DC

Question

I have an existing cluster with the following topology:

1. DC Cassandra: 2 nodes
2. DC Solr: 5 nodes

All of the nodes currently use vnodes. I want to disable vnodes in the Solr DC for performance reasons.

According to this document, to disable vnodes:

1. In the cassandra.yaml file, set num_tokens to 1
2. Uncomment the initial_token property and set it to 1 or to the value of a generated token for a multi-node cluster.

Is this all that I need to do? (no repair, no cleanup, no anything?) Seems too good to be true for me.

As for token assignment, should I use the python code found here (for Murmur3) or should I reuse one of the existing tokens from the vnodes that the node currently has?

Answer 1

The only way to disable vnodes is to do: http://www.datastax.com/documentation/cassandra/1.2/cassandra/configuration/configVnodesProduction_t.html
in the reverse. Make a new Solr dc with vnodes off and switch over to it.